1. Field of the Invention
The invention relates to an apparatus for sticking a tape and a method of sticking the tape, particularly to an apparatus for sticking a tape onto a semiconductor wafer and a method of sticking the tape onto the semiconductor wafer in a process of fabricating a semiconductor device.
2. Description of the Related Art
A semiconductor chip requires a step of polishing a back surface of a semiconductor wafer after a variety of circuit patterns are formed on the front surface of the semiconductor wafer. At this time, a polishing step is carried out after a tape is in advance stuck onto the front surface of the semiconductor wafer so as to protect the front surface of the semiconductor wafer on which a variety of circuit patterns are formed.
Further, the semiconductor chip is fabricated through a dicing step for cutting the semiconductor wafer into respective semiconductor chips upon completion of the steps of forming a variety of circuit patters on the front surface of the semiconductor wafer and polishing the back surface thereof. At that time, the dicing step is carried out after the back surface of the semiconductor wafer is in advance stuck onto a tape which is fixed to a frame ring to prevent the individual semiconductor chips from scattering in pieces when the semiconductor wafer is cut. Still further, a so-called WCSP (Wafer Level Chip Size Package) technique has been widely known recently, namely, a semiconductor wafer is packaged as it is, then it is subjected to a dicing, step so as to fabricate individual semiconductor devices.
When a tape is stuck onto a semiconductor wafer, the tape has been conventionally clamped between both ends of the tape in a tape feeding direction and a tape feeding roller and fixed at this state, thereby applying a tension to the tape in a tape feeding direction.
However, in the conventional apparatus for sticking a tape or a conventional method for sticking the tape, since the tape is clamped between both ends of the semiconductor wafer in a tape feeding direction and a tape feeding roller and fixed at this stage when sticking the semiconductor wafer onto the tape, wrinkle or slack is produced on the tape at portion close to the center thereof, or bubbles remain between the semiconductor wafer and the tape. As a result, an adhesive strength between the tape and the semiconductor wafer becomes weak, causing a fear that the semiconductor chip or semiconductor device is fallen off from the tape and it is scattered.
The invention is to provide an apparatus for sticking a tape onto a semiconductor wafer and a method of sticking the tape onto the semiconductor wafer capable of sufficiently maintaining an adhesive strength between the tape and the semiconductor wafer, and also capable of reducing a possibility that a semiconductor chip or a semiconductor device is fallen off from the tape.
The apparatus for sticking a tape onto a semiconductor wafer of the invention is characterized in comprising a first tape roll around which a tape is wound, a second tape roll for winding up the tape unwound from the first tape roll, and a taper roller disposed between the first and second tape rolls and having a diameter which is tapered or reduced toward both ends thereof.
Further, the method of sticking a tape onto the semiconductor wafer of the invention is characterized in comprising sticking the tape onto the semiconductor wafer while applying a tension to the tape in a tape feeding direction as well as in a tape width direction.